<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script>
    // 下列有什么错误？ 有一处错误
        // const arr = [
        //   {
        //     username: '小明',
        //     age: 18
        //   }
        // ]
        // const { [username, age] } = arr


        const arr = [
          {
            username: '小明',
            age: 18
          }
        ]
        const  [{username, age}]  = arr
  </script>
</body>
</html>